WO2023095838A1

WO2023095838A1 - Catheter

Info

Publication number: WO2023095838A1
Application number: PCT/JP2022/043391
Authority: WO
Inventors: 隆史伊藤
Original assignee: テルモ株式会社
Priority date: 2021-11-29
Filing date: 2022-11-24
Publication date: 2023-06-01

Abstract

Provided is a catheter that is capable of exhibiting excellent penetration properties and preventing a reduction in guide wire maneuverability.　The catheter (1) comprises a shaft (2) having a lumen (5) that is continuous from the distal end to the base end thereof. The shaft (2) has: a reinforcement body (20) comprising at least one reinforcement wire that is arranged in a tube shape; and a radiopaque distal end marker (30) that is positioned on the distal end side of the reinforcement body (20). The length (A) from the distal end of the shaft (2) to the distal end of the distal end marker (30) in the axial direction (X) of the shaft (2) is shorter than the length (L) of the distal end marker (30) in the axial direction (X).

Description

catheter

The present invention relates to catheters used in lumens such as blood vessels.

In recent years, intraluminal treatments such as blood vessels using catheters have been actively performed because the surgical invasiveness is very low. For example, catheters that are used to selectively introduce into complex branching blood vessels in the body are generally pushed along a guide wire that has been previously introduced into the blood vessel to deliver therapeutic drugs and diagnostic imaging. Agents and the like can be distributed through the lumen. In addition, the catheter has a radiopaque marker placed on the shaft so that the position within the lumen can be recognized from outside the body (see, for example, Patent Document 1).

Japanese Patent Publication No. 2018-516128

In the catheter described in Patent Document 1, the distal end of the support structural member made up of the coil member and braided structure overlaps the marker in the axial direction of the catheter. For this reason, the thickness of the distal end portion of the catheter is increased, which tends to increase the outer diameter of the catheter, possibly deteriorating the penetrability.

Also, when inserting the tip of the catheter into a complex lesion with calcification, the tip of the catheter, which is the leading edge of the catheter, tends to deform. If the lumen of the distal tip is deformed and collapsed, the operability of the guidewire inserted into the catheter is reduced.

The present invention has been made in order to solve the above-mentioned problems, and aims to provide a catheter that can obtain high penetrability and can suppress deterioration in operability of the guidewire.

A catheter for achieving the above object is a catheter comprising a shaft having a lumen communicating from a distal end to a proximal end, the shaft comprising a reinforcing body having at least one reinforcing wire arranged in a tubular shape; and a radiopaque tip marker positioned distally of the tip, wherein the length along the axial direction of the shaft from the distal tip of the shaft to the distal tip of the tip marker is the tip less than the length of the marker along said axial direction.

In the catheter configured as described above, since the tip marker and the reinforcing body do not overlap in the axial direction, it is possible to suppress the thickening of the tip of the shaft and obtain high penetrability. In addition, since the length from the tip of the shaft to the tip of the tip marker is smaller than the length of the tip marker, deformation and collapse of the lumen at the tip of the shaft can be effectively suppressed by the tip marker, allowing insertion into the catheter. It is possible to suppress the deterioration of the operability of the guide wire that is used.

The length along the axial direction from the most proximal end of the distal end marker to the distal end of the reinforcing body is equal to or less than the length along the axial direction from the distal end of the shaft to the distal end of the distal end marker. There may be. This reduces the flexible range between the most proximal end of the tip marker and the most distal end of the stiffener, allowing the catheter to exhibit high penetrability.

The length along the axial direction from the distal end of the shaft to the distal end of the tip marker is equal to or less than the length along the axial direction from the proximal end of the tip marker to the distal end of the reinforcing body. There may be. This reduces the flexible range between the distal end of the shaft and the distal end of the tip marker, thereby suppressing deformation and crushing of the lumen of the distal tip by the distal marker and preventing the guidewire from being inserted into the catheter. Operability can be improved.

The shaft may have a tapered portion in which the outer diameter decreases toward the distal end. This makes it possible to improve the insertability of the shaft into the biological lumen.

The length along the axial direction from the tip of the shaft to the tip of the tip marker may be 0.1 mm or more and 3 mm or less. As a result, the tip marker is brought as close as possible to the tip of the shaft whose position the operator wants to confirm by the X-ray image, and the lumen of the tip tip is deformed by the tip marker while obtaining high position confirmation accuracy by the tip marker. It is possible to effectively suppress the crushing and improve the operability of the guide wire inserted into the catheter.

The length along the axial direction from the most proximal end of the tip marker to the most distal end of the reinforcing body may be 0 mm or more and 0.3 mm or less. This allows the catheter to exhibit high penetrability.

The length along the axial direction from the tip of the shaft to the tip of the reinforcing body may be 25 mm. As a result, the catheter can secure a sufficient length on the distal end side from the distal end of the reinforcing body, so that the distal end portion has a certain degree of flexibility and can exhibit high followability to curved blood vessels.

It is a top view showing a catheter concerning an embodiment. FIG. 4 is a cross-sectional view showing the distal end portion of the catheter according to the embodiment;

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the dimensions in the drawings may be exaggerated for convenience of explanation and may differ from the actual dimensions. Further, in the present specification and drawings, constituent elements having substantially the same functional configuration are denoted by the same reference numerals, thereby omitting redundant description. In this specification, the side of the catheter that is inserted into the biological lumen is called the "distal side", and the side that is operated is called the "proximal side". Further, in this specification, the range "X to Y" includes X and Y and means "X or more and Y or less".

The catheter 1 according to this embodiment is introduced into a blood vessel from the radial artery of the arm, the femoral artery of the leg, or the peripheral artery of the lower limb, is inserted into the artery of the lower limb, and is used for treatment, diagnosis, and the like. Catheter 1 is, for example, a support catheter, but may be a device for other uses. Arteries of the lower extremities are arteries near and more distal to the aortoiliac bifurcation. As shown in FIGS. 1 and 2, the catheter 1 includes an elongated shaft 2, a hub 3 connected to the proximal end of the shaft 2, and a kink-resistant protector 4 provided at the joint between the shaft 2 and the hub 3. have.

The shaft 2 is a tubular member having flexibility, and a lumen 5 is formed inside from the proximal end to the distal end. A guide wire is passed through the lumen 5 when the catheter 1 is inserted into the blood vessel. The lumen 5 can also be used as a passageway for liquid medicines, embolic substances, contrast media, medical instruments, and the like.

Although the effective length of the shaft 2 is not particularly limited, it is preferably 200 mm to 2600 mm, more preferably 400 mm to 2300 mm, still more preferably 600 mm to 2300 mm, and 1500 mm in this embodiment. This allows the catheter 1 to reach the arteries of the lower extremities. The effective length of the shaft 2 is the length of a portion that can be inserted into a blood vessel, a sheath, or the like. In this embodiment, the effective length is the length from the tip of the kink protector 4 to the tip of the shaft 2 . The effective length of the shaft 2 is 1200 mm or more when introduced from the arm artery, 650 mm or more when introduced from the femoral artery, and 300 mm or more when introduced from the distal part of the dorsalis pedis artery or posterior tibial artery. is preferred.

The shaft 2 is composed of a plurality of layers, including an inner layer 10 forming an inner surface 11 of the lumen 5, a reinforcing body 20 arranged radially outside the inner layer 10, and a tip marker 30 arranged at the tip. and an outer layer 40 formed radially outside the inner layer 10 . The radially outer side is the side away from the axial center of the shaft 2 .

The inner diameter of the inner layer 10 is substantially constant in the axial direction X, but may vary. The inner diameter of the inner layer 10 is not particularly limited, but is preferably 0.3 mm to 1.2 mm, more preferably 0.4 mm to 1.1 mm, still more preferably 0.4 mm to 0.55 mm.

The inner layer 10 has a lumen 5 formed therein. The constituent material of the inner layer 10 can be a thermoplastic resin, a thermosetting resin, or the like, and is preferably a fluorine-based resin such as polytetrafluoroethylene (PTFE) or a low-friction material such as high-density polyethylene (HDPE). A resin, a polyamide elastomer, a polyester, a polyester elastomer, or the like may be used.

The reinforcing body 20 is formed by braiding a plurality of reinforcing wires 21 into a tubular shape around the outer circumference of the inner layer 10 so as to have gaps. The reinforcing body 20 may be wound with the reinforcing wire 21 while changing the winding direction such as horizontal winding in the same direction, right winding or left winding, and the winding pitch, the inter-grid distance, the inclination angle with respect to the circumferential direction, etc. The configuration is not particularly limited. For example, one reinforcing wire 21 may be coiled in one direction and formed into a tubular shape with a gap. The reinforcement 20 may be placed between the inner layer 10 and the outer layer 40 , but may also be placed within the material of the outer layer 40 or within the material of the inner layer 10 .

The reinforcing body 20 is arranged only partially in the axial direction X of the shaft 2 . The tip of the reinforcing body 20 is located near the tip of the shaft 2 and slightly closer to the proximal side than the tip of the shaft 2 . The proximal end of the reinforcing body 20 is arranged at the proximal end of the shaft 2 or slightly more distal than the proximal end of the shaft 2 .

The wire diameter (diameter) of the reinforcing wire 21 is not particularly limited, but is preferably 0.03 mm to 0.08 mm, more preferably 0.03 mm to 0.06 mm, still more preferably 0.04 mm to 0.06 mm. Yes, and is 0.03 mm in this embodiment.

The reinforcing wire 21 can be made of stainless steel, platinum (Pt), tungsten (W) or other metal wire, resin fiber, carbon fiber, glass fiber, or the like. A round wire, an elliptical wire, or a flat wire may be used. Each reinforcing wire 21 may be used as one wire for braiding, and a bundle of two or more reinforcing wires 21 may be used as one braiding wire. may be used as one line.

The tip marker 30 is a radiopaque (radiographic) circular tube placed at the tip of the shaft 2 . Tip marker 30 is positioned between inner layer 10 and outer layer 40 , within the material of outer layer 40 , or within the material of inner layer 10 . The tip marker 30 is arranged on the tip side of the reinforcing body 20 of the shaft 2 . A length A along the axial direction X from the distal end of the shaft 2 to the distal end of the tip marker 30 is smaller than the length L of the tip marker 30 along the axial direction X.

The thickness T of the tip marker 30 is not particularly limited, but is preferably 0.02 mm to 0.1 mm, more preferably 0.03 mm to 0.08 mm, still more preferably 0.03 mm to 0.04 mm. In the embodiment it is 0.03 mm.

Although the length L of the tip marker 30 along the axial direction X is not particularly limited, it is preferably 0.5 mm to 5 mm, more preferably 0.7 mm to 3 mm, still more preferably 0.7 mm to 2 mm.

The length A along the axial direction X from the tip of the shaft 2 to the tip of the tip marker 30 is not particularly limited, but is preferably 0.1 mm to 3 mm, more preferably 0.1 mm to 2 mm, and more preferably 0.1 mm to 2 mm. It is preferably 0.1 mm to 0.7 mm.

Although the length B along the axial direction X from the most proximal end of the tip marker 30 to the most distal end of the reinforcing body 20 is not particularly limited, it is preferably 0 mm to 3 mm, more preferably 0 mm to 2 mm, and even more preferably 0 mm to 0.7 mm.

In addition, the length B along the axial direction X from the most proximal end of the tip marker 30 to the most distal end of the reinforcing body 20 is not limited to the above example, but is preferably 0 mm to 29 mm, more preferably It may be from 0 mm to 24 mm.

Although the length A+L+B along the axial direction X from the tip of the shaft 2 to the tip of the reinforcing body 20 is not particularly limited, it is preferably 0 mm to 30 mm, more preferably 0 mm to 25 mm.

As a specific example, the length A+L+B along the axial direction X from the distal end of the shaft 2 to the distal end of the reinforcement 20 is 25 mm, and the axial center from the proximal end of the tip marker 30 to the distal end of the reinforcement 20 is 25 mm. The length B along direction X may be 24 mm.

The constituent material of the tip marker 30 is preferably a material kneaded with an X-ray contrast agent such as metal powder of platinum, gold, silver, tungsten, iridium or alloys thereof, barium sulfate, bismuth oxide, or a coupling compound thereof. In addition to being able to use a metal coil or contrast-enhancing solder, it can also be used.

The outer layer 40 is a tubular body arranged around the inner layer 10 . The outer diameter of the outer layer 40 is not particularly limited, but is preferably 0.6 mm to 1.6 mm, more preferably 0.65 mm to 1.4 mm, still more preferably 0.65 mm to 0.9 mm.

The constituent material of the outer layer 40 is, for example, polyolefin (eg, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof), polyvinyl chloride, Polyamides, polyester elastomers, polyamide elastomers, polyurethanes, polyurethane elastomers, polyimides, fluorine resins and other polymeric materials, thermoplastic resins such as mixtures thereof, and thermosetting resins such as epoxy resins can be used. The outer layer 40 may be mixed with an X-ray opaque substance, and the constituent material of the outer layer 40 may be the same as the constituent material of the inner layer 10 .

The shaft 2 has a tapered portion 42 whose outer diameter decreases toward the most distal end. The proximal end of the tapered portion 42 is arranged in the axial direction X at a position coinciding with the tip of the tip marker 30 or on the tip side of the tip of the tip marker 30 . As a result, it is possible to prevent the shaft 2 from being damaged due to excessive thinning of the outer layer 40 arranged radially outward of the tip marker 30 . Note that the proximal end of the tapered portion 42 may be arranged closer to the proximal side than the distal end of the tip marker 30 . This makes it easier to bring the tip of the tip marker 30 closer to the tip of the shaft 2, thereby improving the penetrability.

The length B along the axial direction X from the most proximal end of the distal end marker 30 to the distal end of the reinforcing body 20 is the length A along the axial direction X from the distal end of the shaft 2 to the distal end of the distal end marker 30. is preferably less than or equal to, more preferably less than length A. This reduces the flexible range between the most proximal end of tip marker 30 and the most distal end of stiffener 20 . Therefore, the catheter 2 can exhibit high penetrability.

The length A along the axial direction X from the distal end of the shaft 2 to the distal end of the tip marker 30 is the length along the axial direction X from the proximal end of the tip marker 30 to the distal end of the reinforcing body 20. The length may be less than or equal to B, or may be less than the length B. This reduces the flexible range between the extreme tip of shaft 2 and the tip marker 30 . Therefore, deformation and collapse of the lumen of the distal tip due to the distal marker 30 can be suppressed, and the operability of the guide wire inserted into the catheter 1 can be improved.

The base end of the shaft 2 of the hub 3 is liquid-tightly fixed with an adhesive, heat-sealing, or a fastener (not shown). The hub 3 functions as an insertion port for a guide wire and medical instruments into the lumen 5, an injection port for a drug solution, an embolic substance, a contrast medium, etc., into the lumen 5, and the like, and also serves as a grip when operating the catheter 1. also functions as The material constituting the hub 3 is not particularly limited, but thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer can be suitably used.

The anti-kink protector 4 is made of an elastic material that surrounds the circumference of the shaft 2 and suppresses kinking of the shaft 2 at the connecting portion between the shaft 2 and the hub 3 . For example, natural rubber, silicone resin, polyester elastomer, polyamide elastomer, polyurethane elastomer, etc. can be suitably used as the constituent material of the kink resistant protector 4 .

As described above, the catheter 1 according to this embodiment includes the shaft 2 having the lumen 5 that communicates from the distal end to the proximal end. 21, and a radiopaque tip marker 30 located distal to the reinforcement 20, from the distal tip of the shaft 2 to the tip marker 30. The length A along the axial direction X of the tip marker 30 is smaller than the length L along the axial direction X of the tip marker 30 .

In the catheter 1 configured as described above, since the tip marker 30 and the reinforcing member 20 do not overlap in the axial direction X, it is possible to suppress the thickness of the tip portion of the shaft 2 from increasing and obtain high penetrability. can. In addition, since the length A from the tip of the shaft 2 to the tip of the tip marker 30 is smaller than the length L of the tip marker 30, the tip marker 30 suppresses deformation and crushing of the lumen 5 at the tip of the shaft 2. It is possible to suppress deterioration of the operability of the guide wire inserted into the catheter 1 . Furthermore, since the tip marker 30 can be placed as close to the tip of the shaft 2 as possible, the operator can improve the accuracy of confirming the tip position of the shaft 2 by visually checking the tip marker 30 in the X-ray image.

Also, the length B along the axial direction X from the most proximal end of the tip marker 30 to the tip of the reinforcing body 20 is the length along the axial direction X from the tip of the shaft 2 to the tip of the tip marker 30. It may be A or less. This reduces the flexible range between the most proximal end of the tip marker 30 and the most distal end of the reinforcing body 20, so that the catheter 1 can exhibit high penetrability.

In addition, the length A along the axial direction X from the distal end of the shaft 2 to the distal end of the tip marker 30 is the length along the axial direction X from the proximal end of the tip marker 30 to the distal end of the reinforcing body 20. It may be less than or equal to B. As a result, since the flexible range between the distal end of the shaft 2 and the distal end of the tip marker 30 is reduced, deformation and crushing of the lumen of the distal tip of the catheter 1 by the tip marker 30 is suppressed. It is possible to improve the operability of the guide wire inserted into the.

Also, the shaft 2 may have a tapered portion 42 whose outer diameter decreases toward the tip. Thereby, the insertability of the shaft 2 into the body lumen can be improved.

Also, the length A along the axial direction X from the tip of the shaft 2 to the tip of the tip marker 30 may be 0.1 mm or more and 3 mm or less. As a result, the distal marker 30 is brought as close as possible to the distal end of the shaft 2 whose position the operator wants to confirm by the X-ray image, and the lumen of the distal tip is obtained by the distal marker 30 while obtaining high position confirmation accuracy by the distal marker 30. can be effectively suppressed from being deformed and crushed, and the operability of the guide wire inserted into the catheter 1 can be improved.

Also, the length B along the axial direction X from the most proximal end of the tip marker 30 to the most distal end of the reinforcing body 20 may be 0 mm or more and 0.3 mm or less. Thereby, the catheter 1 can exhibit high penetrability.

Also, the length A+L+B along the axial direction X from the tip of the shaft 2 to the tip of the reinforcing body 20 may be 25 mm. As a result, the catheter 1 can secure a sufficient length on the distal end side from the distal end of the reinforcing body 20, so that the distal end portion has a certain degree of flexibility and can exhibit high followability to curved blood vessels.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art within the technical concept of the present invention. For example, the catheter 1 may have one or more markers other than the tip marker 30 proximal to the tip marker 30 of the shaft 2 . The catheter 1 may also be inserted into bile ducts, trachea, esophagus, urethra, or other biological lumens or body cavities and used for treatment, diagnosis, and the like.

This application is based on Japanese Patent Application No. 2021-193382 filed on November 29, 2021, and the disclosure thereof is incorporated by reference.

1 Catheter 2 Shaft 5 Lumen 20 Reinforcing Body 21 Reinforcement Line 30 Tip Marker 42 Taper Part 51 Marker Arrangement Part 52 Marker Absent Part A Length from the tip of the shaft to the tip of the tip marker B Reinforcement from the most proximal tip of the tip marker Length to tip of body L Axial length of tip marker X Axial direction

Claims

A catheter comprising a shaft having a lumen communicating from a distal end to a proximal end,
the shaft has a reinforcing body comprising at least one reinforcing line arranged in a tubular shape;
a radiopaque tip marker located distal to the reinforcement;
A catheter according to claim 1, wherein the length along the axial direction of the shaft from the distal end of the shaft to the distal end of the tip marker is smaller than the length of the tip marker along the axial direction.
The length along the axial direction from the most proximal end of the distal end marker to the distal end of the reinforcing body is equal to or less than the length along the axial direction from the distal end of the shaft to the distal end of the distal end marker. 2. The catheter of claim 1, wherein a.
The length along the axial direction from the distal end of the shaft to the distal end of the tip marker is equal to or less than the length along the axial direction from the proximal end of the tip marker to the distal end of the reinforcing body. 2. The catheter of claim 1, wherein a.
The catheter according to any one of claims 1 to 3, wherein the shaft has a tapered portion whose outer diameter decreases toward the most distal surface.
The length along the axial direction from the tip of the shaft to the tip of the tip marker is 0.1 mm or more and 3 mm or less, according to any one of claims 1 to 4. catheter.
The length along the axial direction from the most proximal end of the tip marker to the distal end of the reinforcing body is 0 mm or more and 0.3 mm or less, according to any one of claims 1 to 5. Catheter as described.
The catheter according to any one of claims 1 to 6, wherein the length along the axial direction from the tip of the shaft to the tip of the reinforcing body is 25 mm.